key: cord-311026-mpr3xb2a
authors: Petersen, Eskild; Wasserman, Sean; Lee, Shui-Shan; GO, Unyeong; Holmes, Allison H.; Abri, Seif Al; McLellan, Susan; Blumberg, Lucille; Tambyah, Paul
title: COVID-19–We urgently need to start developing an exit strategy
date: 2020-04-29
journal: Int J Infect Dis
DOI: 10.1016/j.ijid.2020.04.035
sha: 
doc_id: 311026
cord_uid: mpr3xb2a

Abstract Aim The purpose of this perspective is to review the options countries have to exit the draconian “lock downs” in a carefully staged manner. Methods Experts from different countries experiencing Corona Virus Infectious Disease 2019 (COVID-19) review evidence and country specific approaches and results of their interventions. Results Three key factors are important: 1. Reintroduction from countries with ongoing community transmission; 2. The need for extensive testing capacity and widespread community testing, and 3. Adequate supply of personal protective equipment, PPE, to protect health care workers. Lifting social distancing is discussed at length. How to open manufacturing, construction and logistics. The opening og higher educational institutions and schools. The use of electronic surveillance is discussed. Conclusion Each country has to decide what is the best path forward. However, we can learn from each other and the approach is in reality very similar.

With the SARS-CoV-2 pandemic passing one million ill people (1,521,252 confirmed cases and 92 798 reported deaths (WHO Sit Rep 10th April) most countries are occupied with controlling the outbreak. The economic consequences are enormous. The World Trade Organization (WTO) estimate that "commerce could shrink up to 32% and warns against 30s-style protectionism" [WTO 2020 ].

With no vaccine and no proven effective treatment, the tools available are limited to social distancing which include quarantine and travel restrictions. These tools are the same as were available during the black death due to plague in Europe in the 13 th century although modern molecular diagnostics and electronic surveillance have modified them slightly.

With no manual to follow most countries have taken a broad approach to slow down the spread of the infection, trying to "flatten the curve" to prevent overwhelming the health care systems by enforcing tight restrictions on population movements. This strategy has effectively "shut own" society and reduced economic activity by closing offices and manufacturing plants, closing schools, restricting mobility in public places, closing nonessential shops, restricting traffic (road, air and sea) and closing borders.

This comes with a heavy socio-economic price, particularly in low-and-middle income countries with limited capacity to absorb prolonged national 'lockdowns'. Many companies have or will file for government support or bankruptcy. Unemployment is rapidly increasing, with devastating consequences on the lives of vulnerable populations, particularly in lowand middle-income countries (LMIC).

It is important to plan for the reactivation of society, restarting work and production, opening up for travels and education. No one knows the future and there have been speculations of "a second wave" which so far is conjectural but may well happen. A strategy or 'roadmap' for deescalating the enforced physical distancing based on epidemiological indicators is needed to inform citizens and policy makers. This review discusses from an epidemiological and medical point of view how strict isolation measures could gradually be lifted. The medical profession must lead the way out of the pandemic just as we shaped the response at the beginning.

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The post peak period -the "opening phase" What is the "post peak period"? There is no clear definition but most experts providing opinions to the media agree that having a plateau of cases or hospital admissions for two weeks signals that the transmission has stabilized and hospitals are able to treat all patients requiring hospitalization for COVID-19 without resorting to crisis standards of care [Zhang J et al. 2020 ]. This is the time when opening up society should be considered. However, because most of the population has not yet been exposed there are concerns that, with minimal but ongoing local transmission, new clusters might escape into the community triggering a second wave of infections [Leung K et al., 2020 ].

In the "post peak" period it will be important to classify the epidemiological situation to increase the understanding of and target transmission and we suggest the following, adapted from the WHO [WHO 19 March 2020] (Table 1) .

There are important lessons from countries such as China and Korea that managed to control the outbreak after experiencing a peak in the first-wave epidemic; Taiwan [Wang et al. 2020] and Macau [Lo et al. 2020 ] which managed to keep case counts low; and places where despite initial control there has been a resurgence such as Singapore and Hong Kong.

The experience from these countries point to three main challenges:

1. Reintroduction from countries with ongoing community transmission (still in the outbreak phase) may initiate a new outbreak in the susceptible population.

2. The need for extensive testing capacity and widespread community testing to identify new cases as early as possible, coupled with effective contact tracing and isolation ability.

3. The importance of adequate supply of personal protective equipment, PPE, to protect health care workers.

The outbreak has demonstrated how easily a respiratory infection can spread across borders. If countries open up for travel before widespread SARS-CoV-2 immunity there need to be interventions to reduce risk of transmission from travelers with few or no symptoms.

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Page 5 of 23 J o u r n a l P r e -p r o o f 5 Post-arrival quarantine has been applied effectively by South Korea, but this is impractical and cannot be implemented in most countries.

We believe that the International Health Regulation, IHR, an agreement between 196 countries including all WHO Member States to work together for global health security, has an important role to play in enforcement of more targeted travel restrictions [IHR 2005 ].

Under the IHR, using a mechanism similar to the Yellow fever immunization certificate requirement, travelers could be asked to provide proof of previous infection, and therefore immunity, by having SARS-CoV-2 specific IgG antibodies [Petersen et al. 2020] . Seronegative travelers could be asked undergo rapid testing (antigen or PCR in the airport pre-departure).

However, rapid testing technologies are not yet available for routine implementation [Petherick A et al. 2020 ].

In Hong Kong, truck drivers are required from the end of this week (9 th April 2020) to produce evidence of a "SARS-Cov-2 negative medical certificate" when they cross the Hong Kong -Mainland border, as required by the Chinese government; these ~10,000 drivers play an important role of ensuring that Hong Kong have food and commodities during the "lockdown".

South Korea imposed two weeks mandatory quarantine on all travelers entering the country from the 1st April; persons with previous infection as documented by positive serology are exempt. This is analogous to healthcare workers who are required to document immunity to varicella, measles, mumps, rubella and hepatitis B before working in most healthcare institutions.

Risk-based approaches to travel restrictions could also be considered. For example, travel restrictions could be eased between countries "past the peak" with local transmission at low levels. For instance, travels between Germany and China could be opened under certain conditions that persons from third countries with high transmission rates would not be eligible for. Another approach could be to open travel from countries with good surveillance systems, transparent reporting, and few local cases where risk of importing infected cases would be low. Opening aviation routes would require agreement between the two countries for direct flights.

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Page 6 of 23 J o u r n a l P r e -p r o o f 6 Lifting the general restrictions on mobility and social distancing allowing business to open, opening schools and higher education institutions, staring manufacturing and allowing travel should be done after peak incidence. However, circulating virus has not disappeared, and resurgence remains a possibility. Determining the rate at which mild disease is spreading in the community is critically important to inform shifts between containment and mitigation strategies.

After de-escalation of enforced physical distancing by closing shops and work places, community-based symptom screening and testing must be made widely available to allow early identification of new cases. This will only be effective if supported by contact tracing, quarantine, and isolation that need supervision by public health authorities. In low-andmiddle income countries it will be essential to provide facilities for quarantine and isolation for people unable to safely do so in their homes.

In the opening phase access to testing on broad indications must be available to all people to allow identification of new cases and clusters as early as possible. This would ideally be supported by point of care tests that are accurate and reliable. There should also be strong systems of surveillance for influenza-like illness, mortality rates, and sick leave.

Public health authorities must be properly staffed and equipped. A recent study from California testing patients with respiratory symptoms found that 11% of influenza-negative were SARS-CoV-2 PCR positive [Zwald ML 2020] and such testing at sentinel sites is an important tool to keep track of community transmission.

Thus, public health capabilities for case identification and isolation must be expanded probably permanently; tools can include physical inspection or use of electronic devices, such as mobile phone-based surveillance and point of care tests as used in Taiwan, Korea and Oman, summarized in table 3.

The examples from Korea, Singapore and Hong Kong show that the virus will re-emerge if strict control measures are relaxed. The closure of all social activities and confining people at home has a profound effect on the economy and should only be maintained until other, An evaluation version of novaPDF was used to create this PDF file. Purchase a license to generate PDF files without this notice. Containment efforts could be focussed on populations at highest risk from infection, including people over 65 years old, people living in care institutions, and those with chronic medical conditions. These groups would need to be identified and supported to restrict their movements and practice social distancing for a longer period than the rest of society.

Communications about such an approach will be critical as the public currently has a strong negative attitude towards any mention of "herd immunity". During times of eased restrictions working from home -"teleworking" -should still be encouraged, and social gatherings discouraged.

Strategies to reduce workplace transmission include daily declarations of being symptomfree by all staff members, and where feasible, screening of staff by RT-PCR or even serology immediately after lifting of enforced quarantine, but the need to screen everyone at a work place before it opens up must be determined individually. This may be particularly important in higher risk industries such as the hospitality sector (tourists and hotels) and aviation or others with high degrees of interaction with vulnerable populations. The occupational health service will be important when manufacturing and construction industries open to keep a very close surveillance on employees and test and quarantine anyone with symptoms pending test results.

Similarly to targeted travel restrictions, opening up shops, offices, school and factories could be preceded by RT-PCR testing of asymptomatic or oligosymptomatic persons and/or introduction of widespread serological testing to confirm immunity prior to removal of individual quarantine. This would require massive mobilisation of resources and is unlikely to be feasible in LMICs in the short term.

It is critical to have communities as partners understanding the need for restriction even while some parts of society start working again. The higher the buy-in and quality of response in every locality, the better the outcome.

Universal masking has been proposed as an additional strategy for reducing community transmission. A surgical masks may reduce risk of community transmission from infected people [Leung CC et al. 2020; Chan KH et al. 2020 ]. This appears to have been effective in An evaluation version of novaPDF was used to create this PDF file. Purchase a license to generate PDF files without this notice.

Page 8 of 23 J o u r n a l P r e -p r o o f 8 countries such as Taiwan and South Korea and parts of Italy where mandatory mask wearing was implemented, although independent impact is difficult to assess. The WHO has recently stated that "the use of a medical mask can prevent the spread of infectious droplets from an infected person to someone else and potential contamination of the environment by these droplets" [WHO 2020e 6 April] and opening workplaces and ask employees to wear a face mask -surgical mask or equivalent -for two weeks after opening is an option which must be discussed with the occupational health service. Lombardy in Italy imposed mandatory face masks in public places [The Guardian 2020] .

We do not know if this will prevent person-to-person spread to the same extent as the closure of shops, factories, educational institutions and offices, but it make sense that masks (including non-medical) will reduce expulsion of large infectious droplets as stated by the WHO, thus reducing the risk of transmission in public spaces.

In China, shops, restaurants, bars, and offices are opening. Manufacturing activity is picking up and traffic starts to flow. Three-quarters of China's workforce was back on the job as of 24 March, according to one company's estimate. Wuhan, where the COVID-19 pandemic originated, is lagging, as is the rest of Hubei province-but even there, the lockdown was lifted the 8th April [Normille D 2020]. The impact of this has yet to be determined.

COVID-19 clusters much more in families and households and social contacts of those households (Fan J et al. 2020 ). More granular geographical information is needed for effective contact tracing, for instance using Geographical Information Systems (GIS). The lesson from South Korea is that tracking of cases and contacts via modern digital technology to apply focused testing can control community transmission without enforced distancing [Korean CDC 2020] . After identifying a case, contacts will be asked to self-quarantine and monitored by appropriate digital technology. Random sampling would help to estimate the number of mild or asymptomatic cases and inform about the true attack rate in the population.

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A well-established and strong core program of infection prevention and control within the healthcare system is central to preparedness and responsiveness. It will also need to be maintained as a priority in the recovery phase of healthcare systems and national exit strategies. As the number of COVID-19 inpatients diminishes and the proportion of inpatients that are COVID-19 naïve rises again, the likelihood of potential nosocomial infection may increase. It is important that there are established hospital surveillance systems that can capture nosocomial infections rapidly and prevent the generation of hospital outbreaks and further waves of transmission.

Hand hygiene and environmental hygiene must be considered as underpinning priorities in protecting healthcare staff, and efforts must be made to promote social distancing in health care settings. The SARS epidemic in Hong Kong demonstrated how vulnerable front line health care workers (HCWs) are. Protecting HCWs is a major task and sufficient personal protective equipment (PPE) must be available [Cheng VCC et al. 2020 ]. The protection of HCWs and support staff is critical, and the resilience of healthcare systems is dependent on sustaining their safety and their trust. In COVID-19 in comparison to SARS, particular attention is needed to ensure that HCWS seeing individuals at the earliest stages in the disease are also well protected, this would include those working in the community and in residential and care homes.

PPE guidelines for healthcare systems need to be clearly communicated, understood, supported by staff and based on best evidence. However, the PPE recommended in any guidance must have the necessary supporting supply chain well defined and clearly mapped, along with the appropriate logistics and the capacity to maintain this. Without continuous adequate, appropriate PPE provision for HCWs and support staff, their sustained commitment and trust required for an effective exit strategy may be lost [Cheng VCC et al. 2020; WHO IPC 2020] . Up to the 27 th March, Singapore had reported a total of 683 cases with 2 deaths. The ministry of health (MOH) had developed a local case definition already by the 2 nd of January 2020 and SARS-CoV-2 real-time polymerase chain reaction (RT-PCR) laboratory testing capacity was scaled up rapidly to all public hospitals in Singapore to handle 2,200 tests a day. All contacts were assessed by telephone for fever or respiratory symptoms by public health officials during the quarantine or monitoring period, thrice daily for close contacts and once daily for contacts at lower risk.

In late January 2020 the following groups were tested for SARS-CoV-2: 1) all hospitalized patients with pneumonia (later expanded to include patients with pneumonia evaluated in primary care settings); 2) ICU patients with possible infectious causes as determined by the physician; 3) patients with influenza-like illness at sentinel government and private primary care clinics included in the routine influenza surveillance network; and 4) deaths from possible infectious causes [Ng Y et al. 2020 ].

Despite the city state's strict contact-tracing, quarantining and travel restrictions, a second wave of infections from returning residents and local transmissions saw cases spike from 100 to 1,000 in one month (SCMP 3 rd April). The initial part of the second wave of infections involves Singapore residents returning from countries such as the United States and Britain.

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Page 12 of 23 J o u r n a l P r e -p r o o f 12 The second wave also includes an increasing number of locally transmitted infections and cases with no known links to confirmed patients. In response to the second wave, the city state introduced stricter social distancing measures, barring the entry of all travellers closing bars and nightlife, and eventually introducing a strict lockdown in early April 2020 with schools, non-essential shops, places of worship etc. closed for a month as locally transmitted cases routinely exceeded a hundred a day.

In Hong Kong, the first imported case of COVID-19 was reported on 23 Jan. 2020, two days before the Lunar New Year. From the last week of January 2020 the Government had ordered closure of schools while most borders with Mainland China were closed from the first week of February. Between February and April control measures were stepped up.

Ordinance (Cap 599), compulsory quarantine and social distancing orders became enforced.

Quarantine covers all people including local citizens entering Hong Kong. Social distancing regulations include prohibition of gathering of more than 4 persons in public areas, restriction of number of customers and the occupancy of catering premises, closure of amusement game centres, bathhouses, fitness centers, bars and other entertainment places. There is no legal restriction on workplaces but the Government has, since late January, mandated work-from-home arrangement for civil servants. However, vacation of workplaces affected not only the 170,000-strong government staff-force but also employees of statutory bodies, non-government organizations as well as major businesses. As of 9

April, 974 confirmed cases of SARS-CoV-2 infection were reported in the 7-million population city, with 4 deaths [Government of Hong Kong 2020]. Some 60% were imported cases or their contacts while local transmission especially dormitories with migrant workers accounted for the rest. Over half of the non-imported cases could be traced back to their close contacts with reported local cases. There was marked increase of daily reports from less than 10 in January/February to 20-60 since the second half of March, which was attributed to the return of local citizens following acceleration of the European outbreaks, and the scaling up of testing. The main local transmission clusters had occurred in a religious worship area and social activities including dinner gatherings and entertainment bars.

Transmission linked to contacts in workplace has so far been uncommon. Universal masking An evaluation version of novaPDF was used to create this PDF file. Purchase a license to generate PDF files without this notice.

Page 13 of 23 J o u r n a l P r e -p r o o f 13 in public areas and on public transport is a common sighting, and in fact forms part of the general hygiene advice. Such practice is required by law for staff and people patronizing catering premises, as stipulated in the newly enacted legal regulation. While the epidemic appeared to be less severe than other cities/countries in the region, restrictions have continued to be tightened to guard against major outbreaks.

Taiwan enhanced COVID-19 case finding by proactively seeking out patients with severe respiratory symptoms (based on information from the National Health Insurance (NHI) database who had tested negative for influenza and retested them for COVID-19 found of 113 cases. The toll-free number 1922 served as a hotline for citizens to report suspicious symptoms or cases in themselves or others; as the disease progressed, this hotline has reached full capacity, so each major city was asked to create its own hotline as an alternative. It is not known how often this hotline has been used. The government addressed the issue of disease stigma and compassion for those affected by providing food, frequent health checks, and encouragement for those under quarantine. This rapid response included hundreds of action items.

Taiwan citizens' household registration system and the foreigners' entry card allowed the government to track individuals at high risk because of recent travel history in affected areas. Those identified as high risk (under home quarantine) were monitored electronically through their mobile phones. On January 30, the NHA database was expanded to cover the past 14-day travel history for patients from China, Hong Kong, and Macau. On February 14, the Entry Quarantine System was launched, so travelers can complete the health declaration form by scanning a QR code that leads to an online form, either prior to departure from or upon arrival at a Taiwan airport. A mobile health declaration pass was then sent via SMS to phones using a local telecom operator, which allowed for faster immigration clearance for those with minimal risk. This system was created within a 72-hour period. On February 18, the government announced that all hospitals, clinics, and pharmacies in Taiwan would have access to patients' travel histories.

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South Africa is an upper-middle income economy with a population of approximately 59 million people and one of the highest inequality rates in the world. Critical concerns are the large population of people living in densely populated peri-urban areas with poor social circumstances plus the high national prevalence of HIV and TB, which may interact with SARS-CoV-2 to cause more severe disease. In addition, South Africa's health services are already overburdened with limited capacity to absorb a large influx of COVID-19 patients.

The first case of COVID-19 was detected on 5 March 2020 in a group of travelers from Italy and the initial period of the epidemic was limited to imported cases and their contacts, occurring within a specific demographic of more middle class and relatively younger people.

The Government responded rapidly, announcing a national state of disaster on 15 March after 61 confirmed cases had been reported with evidence of local transmission (Figure 2 ). This initial public health response included travel bans from countries with high levels of community transmission and 14-day mandatory quarantine for all returning travelers from those countries; school closures; cancellation of gatherings of more than 100 people; and expanding testing and isolation capacity. One week after these measures were implemented, and after case numbers had grown six-fold to 402 cases, a strict national 3week lockdown beginning 26 March was initiated, which prohibited all movement for citizens not involved in designated essential services "except under strictly controlled circumstances, such as to seek medical care, buy food, medicine and other supplies or collect a social grant." Despite the profound impact of the lockdown on an already tenuous economy -estimated reduction in growth by 2.6% translating into ~9% contraction of national GDP -the President announced a 2-week extension on 9 April, following an apparent reduction in the average daily infection rate from 42% to 4%. Critical challenges for transitioning to a risk-based containment strategy in South Africa include limited testing capacity -currently 75,000 tests have been performed; matching the per-capita testing of South Korea would require 400,000 tests -and lack of infrastructure to implement contact tracing and isolation for people living in dense peri-urban environments.

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Each country has to decide how to open up society for work and social activities. A study comparing health care systems in Hong Kong, Singapore and Japan had three important conclusions [Legido-Quigley et al. 2020 ]. The first is that "integration of services in the health system and across other sectors amplifies the ability to absorb and adapt to shock".

The second is that "the spread of fake news and misinformation constitutes a major unresolved challenge". Finally, "the trust of patients, health-care professionals, and society as a whole in the government is of paramount importance for meeting health crises". While the surge of cases in these three countries may have altered the analysis somewhat, the general principles still apply. This is a new infection spreading in a nonimmune population and we have no manual -yet we have to take decisions. Measures that can be used are summarized in table 4. As each country chooses its own path, we can learn from each other to determine the optimum approach that works in our setting.

Funding. The study received no funding Table 2 . A reopening of society should be staged according to the local situation

Restrictions lifted for a specific sector of the society.

Could be schools, could be certain manufacturing industries, construction industry.

Could be limited to low endemic areas only.

Observe for 2 weeks, monitor hospital admissions, perform testing at sentinel sites and all persons with upper and lower respiratory tract infections.

Extend opening of manufacturing and construction industries

Open public transport but request face mask in public spaces

Open schools in more areas

Open international travels from selected countries, quarantine arrivals from high endemic countries or perform rapid DNA test on arrival

Observe for 2 weeks, monitor hospital admissions, perform testing at sentinel sites and all persons with upper and lower respiratory tract infections.

Open small shops and restaurants provided social distancing is maintained.

Open international travels from selected countries, quarantine arrivals from high endemic countries or perform rapid DNA test on arrival.

Observe for 2 weeks, monitor hospital admissions, perform testing at sentinel sites and all persons with upper and lower respiratory tract infections.

Open up for mass gatherings like football matches, religious gatherings etc. . . . . Table 3 . Generic electronic surveillance system.

The system use information from mobile phones or bracelets.

The system is linked to a national electronic surveillance system and to the civil identification number and can be shared with other stakeholders such as police or public prosecution.

An "Isolation Enforcement System" can provide supervision of location of persons in isolation or quarantine outside institutions. Isolation Tracking App Isolation Compliance Crowdsensing when people in quarantine move out of the isolation facility Mobile phone and/or bracelet App Self Reporting and symptoms analysis Self Reporting Questionnaires Translation and language support The bracelet is for a single-use purpose that makes it very cost-effective and will be able to measure the body temperature

The system will allow authorities to Supervise compliance with quarantine and isolation Anti-temper 12-month battery life Perform Contact history by linking geographical location of SIM card or bracelet risk assessment according to the number of people quarantined or isolated in a specific geographical location.

An evaluation version of novaPDF was used to create this PDF file. Purchase a license to generate PDF files without this notice. Table 4 . Principles can help countries to plot a way out of the shutdown.

1. Consider easing restrictions when the case count has decreased after the peak, has been stable for 2 weeks and the hospitals can cope with the number of serious cases.

Cases must be staged into imported, linked to known clusters and cases and unknown source.

2. Expand testing for new and past infections by setting up sentinel testing sites, introduce testing stations in the community providing diagnostic tests to everyone with compatible symptoms and serological testing for surveillance of population immunity. Introduce point-of-care (POC) testing when validated tests become available.

3. Consider testing employees with nucleic acid tests and/or antibody test prior to return to work to find silent cases and recovered persons. This can be applied to schools also.

In collaboration with the occupational health service establish sustainable workplace policies emphasizing infection control.

4. Consider imposing the use of surgical or non-medical face masks whenever outside the household to reduce risk that persons with an unrecognized infection will contribute to transmission. This must be an adjunct to other ongoing social distancing interventions and hand hygiene.

5. Continue to impose quarantine on arriving passengers from countries with active outbreaks. Aim to develop a travel certificate for people with documented immunity with SARS-CoV-2-specific antibodies to be exempt from quarantine rules.

6. Maintain strong infection prevention measures in all health care institutions 7. The SARC-CoV-2 virus will most probably be in our societies for a long time until we have a vaccine. Flare ups, small outbreaks and clusters is expected and thus the public health care system must be developed to take care of new cases, rapidly perform case and contact follow up and ensure quarantine. Thus, a permanent upgrade of the public system is needed.

COVID-19 epidemic: disentangling the re-emerging controversy about medical facemasks from an epidemiological perspective

Escalating infection control response to the rapidly evolving epidemiology of the Coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 in Hong Kong

Epidemiology of 2019 Novel Coronavirus Disease-19 in Gansu Province, China, 2020. Emerg Infect Dis. 2020;26:6. Government of Hong Kong

Lombardy insists on face masks outside homes to stop Covid-19. Angela Giuffrida in Orvieto and Peter Beaumont

Impact of school closures for COVID-19 on the US healthcare workforce and net mortality: a modelling study

Middle East Respiratory Syndrome Coronavirus Outbreak in the Republic of Korea

Disease Control and Prevention. The updates of the COVID-19 in the Republic of Korea

Epidemiology and Case Management Team. Contact Transmission of COVID-19 in South Korea: Novel Investigation Techniques for Tracing Contacts

Guideline for COVID-19 Response

Interrupting transmission of COVID-19: lessons from containment efforts in Singapore

Are high-performing health systems resilient against the COVID-19 epidemic?

Mass masking in the COVID-19 epidemic: people need guidance

First-wave COVID-19 transmissibility and severity in China outside Hubei after control measures, and second-wave scenario planning: a modelling An evaluation version of novaPDF was used to create this PDF file. Purchase a license to generate PDF files without this notice. impact assessment. The Lancet 2020

Evaluation of SARS-CoV-2 RNA shedding in clinical specimens and clinical characteristics of 10 patients with COVID-19 in Macau

Evaluation of the Effectiveness of Surveillance and Containment Measures for the First 100 Patients with COVID-19 in Singapore

Can China return to normalcy while keeping the coronavirus in check?

The Korean Middle East Respiratory Syndrome Coronavirus outbreak and our responsibility to the global scientific community

COVID-19 travel restrictions and the International Health Regulations -call for an open debate on easing of travel restrictions

Developing antibody tests for SARS-CoV-2

Coronavirus Singapore: 100 to 1,000 infections in one month. What happened? 3 rd

The Government of the Republic of Korea. Tackling COVID-19. Health, Quarantine and Economic Measures: Korean Experience

Response to COVID-19 in Taiwan: Big Data Analytics, New Technology, and Proactive Testing

Operational considerations for case management of COVID-19 in health facility and community. Interim guidance

WHO Situation Report-72. 1 st

Advice on the use of masks in the context of COVID-19. Interim guidance. Geneva 6 th

Coronavirus disease (COVID-19) technical guidance: Infection prevention and control / WASH. Collection of documents

An evaluation version of novaPDF was used to create this PDF file

Trade set to plunge as COVID-19 pandemic upends global economy

Evolving epidemiology and transmission dynamics of coronavirus disease 2019 outside Hubei province, China: a descriptive and modelling study

Rapid Sentinel Surveillance for COVID-19

Table 1. Classification of new cases during surveillance in the

Imported, i.e. likely infections abroad B. Part of known cluster, or contact to known case C

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All authors contributed equally to the text.An evaluation version of novaPDF was used to create this PDF file. Purchase a license to generate PDF files without this notice.Page 16 of 23 J o u r n a l P r e -p r o o f
